It measures roughly seventeen metres east to west and fifteen metres north to south, yet rises only about fifteen centimetres above the surrounding ground. To a passing eye it is easy to dismiss as a trick of the terrain. It is, in fact, a fulacht fia, one of the most common and least understood monument types in the Irish archaeological landscape.

A fulacht fia, sometimes called a burnt mound, is the remains of an ancient cooking or industrial site, typically Bronze Age in date. The characteristic crescent or horseshoe-shaped mound is formed from the accumulated debris of a repeated process: stones were heated in a fire and then dropped into a water-filled trough to bring it to the boil. The shattered, fire-cracked fragments were scooped out and piled to the side after each use, and over generations those discarded stones built up into the low, scorched mound visible today. What makes the Ballyhoolahan Middle site quietly notable is not just its own presence but the fact that a second fulacht fia lies approximately ten metres to the south. Two such monuments in such close proximity raises questions that archaeology has not fully settled: were they used simultaneously, by different groups, or for different purposes? The pairing is a small but genuine anomaly in a county already dense with these features.